biil9

good morning guys. I put a 1 inch spacer on my 89 mustang intake to accept a plenum from an explorer on my cobra kit car. I had already bolted it on and torqued it before I realized I had a clearance issue with the valve covers. now with the spacer on I put the longer bolts provided with the kit and as I snugged the first bolt a crack appeared just above the bolt hole. I need to fix it and I need to fix it right. epoxy,tig welding? what do u think? thanks guys. it was torqued below the highest recommended rate so I never once overtightened it. I'm thinking it was stressed from the past.

dawson1112

epoxy is not an option , the crack will continue to grow with time. Even just welding it will likely present issues later on down the road. It will need to be ground out to find the ends of the crack have relief holes drilled in the very ends of the crack then welded. It would be much better to just replace it. Ive had a lot of years dealing with aluminum welding, and cast aluminum once it cracks will 99% of the time continue to worsen. It takes quite a bit of experience with welding to repair a crack in cast aluminum .

biil9

not what i wanted to hear but i guess i dont have a choice. thank you

dawson1112

Yea Im sure its not. Im not saying it cant be done by a highly skilled welder, but by the time you factor in the cost of the repair, vs the cost of a used explorer intake, then the likely hood that the repair will fail at some point... A used intake seems like the best option to me.

Maxwelhse

Not to ignore Dawson's advice, because I believe that replacement is the most "correct" solution, but I'd JB weld that thing, fit up a steel washer to JB weld over the top of the boss too, and call it a day...

You're not talking about something hyper critical here. If it fails, even badly, it's going to probably just create a vacuum leak. Since you know about the problem, it will make it an easy place to check first.

JB weld, then look for a higher performance replacement to swap out later.

biil9

thank you for your reply. i am taking it to an old school welder who says he can repair it correctly. the only thing i dont know yet is the cost. thank you again

Maxwelhse

Old school, new school, before school, or in detention, cast materials are a nightmare to weld and aluminum just takes it to a new level. I'm not much of a welder myself, but I've had the privilege of spending about 10 years next to real pros... One of the most talented welders I've ever met used to repair cast aluminum blow molding molds with epoxy putty since its the only thing that would work.

I think you're probably throwing good money after bad on this one. Buy $5 of JB Weld, get it in a stable operating condition, save your pennies for a Trick Flow or Holley... I've got to think in the kit Cobra world that you would be a stand out for having REAL performance hardware on your 5.0... You'd get extra credit from me anyhow.

Most of all, good luck! The trouble your in now is classic hot rodding (...I'll MAKE it work), and most folks don't even know what the means anymore!